There are not many people who'll stand up for the rioters and the looters at the moment, but I'll give it a shot. I don't want to stand up for the rioting and the looting, merely recognise that when people feel powerless, have no opportunities, and have nothing to lose, it doesn't take much for them to step into lawlessness. We live in a country with great disparities between rich and poor, where a right-wing goverment is seen to be hitting the poorest hardest, and where a rabid right-wing press talks constantly about scroungers and chavs. The question shouldn't be "Why are they rioting?", but rather "Why aren't they rioting more often?"
Most people can't put themselves in the shoes of the rioters. They can't imagine having nothing to lose. They only find their individuality lost to the crowd in the relatively safe environments of concerts or football matches, rather than in Tottenham at night amongst a crowd who feel equally persecuted. Yet people are quick to say they wouldn't behave that way, or to continue the Daily Mail's discourse about the working class scum, the need to repeal the human rights act, and calling for water-cannon on the streets of London.
The right are equally products of their environment, the difference is that they have far more opportunity to escape their ignorance...yet amazingly few choose to do so.